Ok. Well, here are a few P-headed combos in our dyno & 1/4 mile thread:
- v8stang289's combo: 277 RWHP, but ran a best trap of 101.6mph @ close to stock weight (not the kind of speed I'd expect)
- Grabbin' Asphalt: 280 rwhp (Cobra intake & Gt40p heads both fully ported & milled with an E-cam - no slips to back it up, but porting makes this feasible)
- RangerJoe: 268rwhp (Ported Cobra, Iron GT40's TFS1 with 1.77rr & he's run at least a [email protected] backing up his dyno)
- Michael Nadeau: 244rwhp (Ported GT40 intake, GT40Ps, N41 cam, but the claim 1/8 mi suggests more (or lighter) than what the dyno shows: 8.41 @ 86.4 mph more than backing up the dyno)
- foureyefox347: 109.93 mph (347 c.i. Gt40p ported, 650 holley on a Edelbrock rpm intake). Probably in the 300 rwhp range
- Bob F: 273 rwhp (GT40p heads, ported Cobra intake, stock cam - only 99.5 mph suggesting nothing like the dyno'd rwhp unless it's in a bus)
- 86HO5.0: 281 rwhp (Ported explorer intake, P-heads, stock cam - I have to be honest... no way in hell. No timeslips to back it up, but has provided some datalogs of a couple of pulls that I can do some analysis on. Sometimes dyno's are just happy, especially SAE corrections)
- Chuckman: 264rwhp (Stock '01 Explorer longblock (P-heads + GT40 intake, tfs stage1 cam, claimed he trapped in the 100-101 range)
So, what do we get out of all of that? If you just slap unported P-heads on then you might only run 101-ish mph in the 1/4. With proper tuning & supporting mods (cam-intake-induction) maybe 260 rwhp range, which is not much, maybe 10-15rwhp, shy of what the aluminum X-headed combos tend to make.
- v8stang289's combo: 277 RWHP, but ran a best trap of 101.6mph @ close to stock weight (not the kind of speed I'd expect)
- Grabbin' Asphalt: 280 rwhp (Cobra intake & Gt40p heads both fully ported & milled with an E-cam - no slips to back it up, but porting makes this feasible)
- RangerJoe: 268rwhp (Ported Cobra, Iron GT40's TFS1 with 1.77rr & he's run at least a [email protected] backing up his dyno)
- Michael Nadeau: 244rwhp (Ported GT40 intake, GT40Ps, N41 cam, but the claim 1/8 mi suggests more (or lighter) than what the dyno shows: 8.41 @ 86.4 mph more than backing up the dyno)
- foureyefox347: 109.93 mph (347 c.i. Gt40p ported, 650 holley on a Edelbrock rpm intake). Probably in the 300 rwhp range
- Bob F: 273 rwhp (GT40p heads, ported Cobra intake, stock cam - only 99.5 mph suggesting nothing like the dyno'd rwhp unless it's in a bus)
- 86HO5.0: 281 rwhp (Ported explorer intake, P-heads, stock cam - I have to be honest... no way in hell. No timeslips to back it up, but has provided some datalogs of a couple of pulls that I can do some analysis on. Sometimes dyno's are just happy, especially SAE corrections)
- Chuckman: 264rwhp (Stock '01 Explorer longblock (P-heads + GT40 intake, tfs stage1 cam, claimed he trapped in the 100-101 range)
So, what do we get out of all of that? If you just slap unported P-heads on then you might only run 101-ish mph in the 1/4. With proper tuning & supporting mods (cam-intake-induction) maybe 260 rwhp range, which is not much, maybe 10-15rwhp, shy of what the aluminum X-headed combos tend to make.
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